Performing the border: Mapping smuggling and state sovereignty in the Grand Duchy of Lithuania-Prussia borderlands

Scholars of borders and boundary-making have long emphasized that frontiers are not inert lines on maps but historically contingent, socially produced, and continually negotiated spaces. This article revisits the late eighteenth-century frontier between the Grand Duchy of Lithuania (GDL) and Prussia to examine how sovereignty was enacted and contested through customs enforcement and smuggling. We distinguish boundary (a legal framework) from border (lived practices) and situate the case within the gradual European ‘linearization’ of boundaries. Empirically, we expand the analysis of what was smuggled, by whom, and to what ends—ranging from subsistence-level crossings by peasants to long-distance trading networks funnelling timber to Prussian shipyards. Methodologically, we blend topographical mapping (locating posts, roads, and reported paths) with topological visualization (modelling relations among nodes) to make visible the evolving performance of the border. Two Treasury inspection tours—Jerzy Leparski (1769) and Michał Kleofas Ogiński (1788)—bookend a formative moment of customs reorganization under the GDL Treasury Commission. Read together, they reveal a shift from conspicuous, locally known smuggling paths to more concealed routes as the customs system densified (from roughly two dozen to nearly fifty posts in our study area) and moved closer to the frontier.